14 WELLS's NATURAL PHILOSOPHT. 



the 8,G40,000th part of an ounce. "We may divide this inch into one hundred 

 pieces, and yet see each piece distinctly without the aid of a microscope : iu 

 other words, we see the 864,000,000th part of an ounce. If we now use a 

 microscope, magnifjing five hundred times, we may clearly distinguish the 

 432,000,000,000th part of an ounce of gold, each of which parts will bo found 

 to have all the characters and qualities which are found in the largest masses 

 of gold. 



Some years since, a distinguished English chemist made a series of experi- 

 ments to determine how small a quantity of matter could be rendered visible 

 to the eye, and by selecting a peculiar chemical compound, small portions of 

 ■which were easily discernible, he came to the conclusion that he could dis- 

 tinctly see the billionth part of a grain. 



In order to form some conception of the extent of this subdivision of mat- 

 ter, let us consider what a billion is. We may say a billion is a million of ' 

 miUions, and represent it thus, 1,000,000,000,000; but the mind is incapable 

 of conceiving any such number. If a person were to count at the rate of 200 

 in a minute, and work without intermission twelve hours in a day, he would 

 take, to count a billion, G,944,944 days, or more than 19,000 years. But this 

 may be nothing to the division of matter. There are living creatures so mi- 

 nute, that a hundred millions of them may be comprehended in the space of 

 a cubic inch. But these creatures, until they are lost to the sense of sight, 

 aided by the most powerful instruments, are seen to possess arrangements 

 fitted for collecting their food, and even capturing their prey. They are there- 

 fore supplied with organs, and these organs must consist of parts correspond- 

 ing to those in larger animals, which in turn must consist of atoms, or little 

 particles, if we please so to term them. In reckoning the size of such atoms, 

 we must not speak of billions, but of billions of billions. Such a number can 

 be represented thus, 1,000,000,000,000,000,000,000,000, but the mind can 

 form no rational conception of it.* 



13. We use the term Molecules, or Pak- 

 I^t'o^plrH- TiCLES of matter to designate very small quan- 

 cies of Matter? ^-j^jgg ^f g^ substaiice, Hot meaning, however, the 

 ultimate atoms. A molecule, or particle of matter may- 

 be supposed to be formed of several atoms united to- 

 gether. 



14. No two atoms of matter are supposed to 

 touch, or be in actual contact with each other, 



and the openings or spaces which exist between them are 



called Pores. This property of bodies, according to which 



their atoms are thus separated by vacant places^ 



What U^Poros- ^^ ^^jj PoROSITY. 



* The billion is here used according to the English notation. — Viae Webstar. 



